1. Field of the Invention
This invention is in the field of toothbrushes used for the care and cleaning of teeth and gums, particularly to a toothbrush having a bristle arrangement comprising at least two rows of bristles grouped in bundles, each independently anchored into a base (also referred to herein by the term toothbrush “head”). Although two rows of bundled bristles are most preferred in the present invention, it is considered within the scope of the present invention to have more than two rows of bundled bristles. Thus, for convenience and language efficiency in the disclosure herein, embodiments with two rows of bundled bristles will most commonly be discussed, without any intent of limitation.
The bundles of bristles in each row of the present invention are directed inwardly toward the other row and positioned at an angle of common intersection, such that substantially all of the free tip ends of the bristles terminate in a single, common row. Although not critical, the common row is most often longitudinal, and centered laterally on the toothbrush head, as shown in the accompanying illustrations. In addition, the bundles of bristles in each row are preferably soft, and anchored in alternating relation to the bundles of bristles in the opposing row. Thus, the free tip ends of each bundle of bristles are unopposed and terminate independently to become part of the single, common row of bristles. Also, the tip ends in each bundle of bristles remain free standing, allowing each bristle to have movement independent of the bristles in the next adjacent bundle or bundles. As a result, and importantly, it is this independent arrangement of inwardly directed bundles of bristles positioned in alternating relation to the bundles in the opposing row that makes each bundle of bristles free standing, enabling a different angle of attack for the bristles therein relative to the movement of bristles in adjacent bundles, resulting in less tooth abrasion during use when compared to the toothbrushes commonly used today.
2. Description of the Related Art
Today's toothbrushes comprise a collection of many bundles of bristles, each bundle separated from the others in the brush base holder, each bundle having a column-shaped configuration, and each bundle aligned in rows with neighboring bundles. Although such toothbrushes serve well and are commonly used, an important disadvantage to their use is abrasion of the rounded outward facing part of the tooth structure, particularly the rounded part at or near the gingival level. With regard to the aging process of human teeth, if people live long enough they will eventually experience recession of the gum and notching of teeth at the gum line. The notches are not decay, but are treated as such and filled with a composite resin restoration. Notching is a common occurrence in elderly patients, and treated by dentists on a daily basis. If untreated, the notches progress, and may eventually advance down to the tooth's nerve. During their teeth cleaning use, toothbrush bristles tend to hit the closest thing to them, when, in fact, it is more important for people to target the area between the teeth during cleanings. Thus, the part of the tooth facing most outward from the mouth is typically cleaned first by toothbrush bristles, before the bristles are pressed further into the interproximal areas. As a result, the curved outward facing part of teeth will bear the force of the toothbrush bristles twice, initially and also during the cleaning of interproximal areas. Thus, over time tooth brushing wears down the outward facing tooth structure. When the bristles are pressed further into the interproximal areas, the aligned bundles of bristles in today's toothbrushes serve detrimentally as they become compressed against the outward facing tooth surface, and the bundles each act as a column, with added force being applied against the rounded/curved outward part of the teeth to overcome the strength of the column and splay the bristle tip ends to direct them around the teeth and into the deeper interproximal areas. Thus, when considering the detrimental abrasion it causes to the rounded/curved and outward facing part of the tooth structure, today's toothbrushes can be said to have an inefficient design, leaving much room for improvement.
In contrast to the known prior art, the bundles of bristles in each row of a present invention toothbrush are anchored in alternating relation to the bundles of bristles in the opposing row. Thus, the free tip ends of each bundle of bristles in a present invention toothbrush remains free standing, allowing each bristle to have movement independent of the bristles in the next adjacent bundle or bundles. As a result, and importantly, the free standing positioning of each present invention bundle of bristles enables a different angle of attack for the bristles therein relative to the movement of bristles in adjacent bundles, resulting in less force being applied to tooth surfaces and less tooth abrasion to the rounded/curved and outward facing part of the tooth, particularly at or near the gingival level. While other dental brushes are known to include angulations of bristles to a single common free end, all are in a linier arrangement and poise the free tip ends of one group of angled bristles directly into those of an opposing group. This convergence of bristles from the opposed rows at a single point creates the important disadvantage of causing more wear on the rounded outward facing tooth surfaces when the cleaning of difficult-to-reach interproximal areas is attempted, since all bristles in a bundle then behave as a unit, dampening the full function of each individual angled bundle of bristles and applying more force to the closest tooth surfaces. As a result during teeth cleaning with prior art dental brushes having opposed groups of bristles, teeth become notched at the gum line an accelerated rate when compared to teeth cleaning conducted with the present invention toothbrush. No prior art dental brush intended for the general cleaning of tooth surfaces, as well as interproximal areas, is known to provide alternating groups of bundled bristles having substantially all their bristle tip ends directed inwardly and positioned at an angle of common intersection for termination in a single common row, as found in the present invention, which has been observed by the inventor herein during its development to reduce wear on the rounded outward facing tooth surfaces, particularly at or near the gum line.